1. Field of the Invention
The present invention relates to a spectroscopy device for spectrally separating inputted light, and a spectroscopy apparatus and method using the same.
2. Description of the Related Art
As for spectroscopy devices, spectroscopy apparatuses, and spectroscopy methods, various structures are known. But, in general, they spectrally separate input light using a prism, and record the separated light beams after converting to electrical signals using an image sensor. Conventional spectrophotometers structured in the manner as described above have difficulty to detect a plurality of wavelengths at the same time, because a change in the wavelength to be separated corresponds to a mechanical change in the drive mechanism of the prism. Consequently, the following inventions have been made to solve this problem.
Japanese Unexamined Patent Publication No. 8 (1996)-193884 discloses a spectroscopy apparatus having the following disposed serially on the optical path in the order of: a first imaging lens, a slit plate, a first collimator lens, a spectroscopy means, a second collimator lens, a microprism array, a second imaging lens, and a two-dimensional array sensor. A light beam having a predetermined wavelength of those separated by the spectroscopy means is deflected by the microprism array and outputted in a predetermined direction. This causes a spectroscopic image to be formed on a predetermined sensor of the two-dimensional array sensor, whereby a spectroscopy apparatus capable of obtaining multitudes of spectra at the same time is realized.
U.S. Pat. No. 5,729,011 discloses a spectroscopy apparatus in which a field mask and a plurality of light refraction surfaces having normal lines in directions different from the directions of the optical axis of the optical system are formed, and a prism is disposed adjacent to the pupil surface of a lens such that the pupil surface of the lens is divided by each refraction surface, in addition to a lens and an image sensor. This causes a plurality of the same images generated on the image sensor to be formed as a plurality of the same spectroscopic images having a different wavelength component from each other, whereby a spectroscopy apparatus capable of obtaining spectroscopic images corresponding to a plurality of wavelengths at the same time is realized.
These spectroscopy apparatuses require an optical system including a prism and a lens for the image sensor imaging a spectroscopic image, so that a large space is required in terms of component arrangement or optical design. Consequently, the size of these spectroscopy apparatuses becomes very large. Further, components including the prism, lens, and image sensor are aligned over the housings, so that a prolonged time is required for the adjustment and the alignment accuracy is also limited.
It is an object of the present invention, therefore, to provide a novel spectroscopy device which is free from those problems found in the conventional spectroscopy devices, spectroscopy apparatuses, and spectroscopy methods.